The reason to use a good quality wire stripper is to keep from scrapping the wire you are stripping, you want to remove the insulation without damaging the wire itself.
When I worked at McDonnell Douglas damaging a wire being stripped was important in commercial aircraft, but absolutely critical for military aircraft. At that time most plugs and receptacles on military aircraft were soldered and wire nicks were absolute no-no's.
You had to be a certified solderer to work on military aircraft and it wasn't easy to pass certification.

